Web Concepts

Posts Tagged ‘satellites’

Maybe next time, Canada

See our gallery of the space race's greatest falls to Earth. (List compiled by Jonathan's Space Report.)

NASA has been tracking UARS for some time now as the decommissioned satellite’s orbit has been decaying. Much of the satellite was expected to burn up on re-entry, but experts estimated that roughly two-dozen pieces of the massive satellite would survive and could potentially be a threat to people or objects on the ground. Given UARS’s speed and the many variables involved (this is a decommissioned satellite, after all, so re-entry was completely uncontrolled) there was no telling exactly when or where UARS might land.

On Saturday, when the final descent began, previous calculations had placed the crash window across a large swath of northwestern North America. The Internet rumor machine fired up and sightings across Canada and the Pacific Northwest proliferated. But by that point updated U.S. Air Force calculations placed the satellite thousands of miles away in another hemisphere, and NASA has confirmed those calculations. UARS is now resting peacefully in the South Pacific, somewhere southwest of Christmas Island were small islands are scattered across a lot of water.

The difference between Seattle and Samoa? Just a few minutes. NASA said UARS came in for its rough landing several minutes earlier than they had projected. What they won’t say is how they know this--they referred those questions to the USAF, which also isn’t talking. Were DoD missile tracking assets employed in tracking UARS? The Air Force would rather not say at this point, but one would think something like this would be good practice.

UARS is not the first piece of man-made space hardware to come crashing back to Earth, and it won’t be the last. In late October or early November a German astronomy satellite will make its uncontrolled final plunge back to Earth. Though smaller than UARS, more pieces are expected to survive re-entry (a total of 30 are expected, possibly including sharp pieces of mirror). Let’s hope that one finds a nice stretch of uninhabited ocean as well.

[AP]

The notion stems from a phenomenon the researchers from Tsinghua University in Beijing noticed from time to time with Jupiter. Every now and then our solar systems biggest planet pulls in an object from space, which orbits the planet for a time before jetting off into interplanetary space again.

We could do something similar with a number of near earth objects (NEOs) that will pass near Earth in the coming years and decades. None of these objects will pass close enough to be naturally captured by Earth’s gravity, but a few will come so close that a small nudge in the right direction would put them in orbit--likely a temporary orbit--around Earth.

The idea isn’t simply to flirt with cataclysmic danger, but to bring a small object (they suggest a 10-meter object called 2008EA9 that will pass nearby in 2049) into a loop around the Earth so we can study it closely for a few years. If we can get the art of capturing asteroids orbitally down to a science, we could use it to temporarily make asteroids into Earth-bound satellites (orbiting at about twice the distance of the moon), mine them for minerals, and then send them on their ways.

Read the paper at arXiv.

[Technology Review]

The sun spewed three CMEs Earthward last week, sending solar particles hurtling toward the planet. The last two combined, resulting in a strong compression of the magnetosphere, NASA said. The double punch was expected to disturb power grids at high latitudes, NASA said.

2011 has already been a big year for solar flares, with a previous CME in February disrupting shortwave communications in China and ship-to-shore radios. That flare led to aurora borealis as far south as Great Britain. Then in June, a relatively smaller flare belched a billion tons of material away from the sun before it collapsed back to the surface.

The first CME already passed the Earth late last week, and the second two are affecting us right now, according to Reuters. The Space Weather Prediction Center at NOAA is forecasting a moderate to strong magnetic storm. The second two flares impacted an already compressed magnetosphere, so additional solar activity could exacerbate the disturbance — or do nothing at all, forecasters said.

It’s all part of the sun’s ramped-up cycle of activity, which is expected to peak sometime in 2013. Scientists have been beating the drum about solar activity preparations as the 11-year solar cycle continues, because a massive flare can disrupt satellites, power grids and telecommunications. Here’s hoping this triple threat is it for a while.

[Reuters]

A solar disaster isn't a question of if, but when--and it looks like soon

Curious about what a CME would mean for us? Check out our feature.

Within weeks, backup generators at nuclear power plants would have run down, and the electric pumps that supply water to cooling ponds, where radioactive spent fuel rods are stored, would shut off. Multiple meltdowns would ensue. “Imagine 30 Chernobyls across the U.S.,” says electrical engineer John Kappenman, an expert on the grid’s vulnerability to space weather. A CME big enough to take out a chunk of the grid is what scientists and insurers call a high-consequence, low-frequency event. Many space-weather scientists say the Earth is due for one soon. Although CMEs can strike anytime, they are closely correlated to highs in the 11-year sunspot cycle. The current cycle will peak in July 2013.

The most powerful CME in recorded history occurred during a solar cycle with a peak similar to the one scientists are predicting in 2013. During the so-called Carrington Event in 1859, electrical discharges in the U.S. shocked telegraph operators and set their machines on fire. A CME in 1921 disrupted radio across the East Coast and telephone operations in most of Europe. In a 2008 National Academy of Sciences report, scientists estimated that a 1921-level storm could knock out 350 transformers on the American grid, leaving 130 million people without electricity. Replacing broken transformers would take a long time because most require up to two years to manufacture.

"We need to build protection against 100-year solar storms."Once outside power is lost, nuclear plants have diesel generators that can pump water to spent-fuel cooling pools for up to 30 days. The extent of the meltdown threat is well-documented. A month before the Fukushima plant in Japan went offline in March, the Foundation for Resilient Societies, a committee of engineers, filed a petition with the U.S. Nuclear Regulatory Commission recommending the augmentation of nuclear plants’ emergency backup systems. The petition claims that a severe solar storm would be far worse than a 9.0-magnitude quake and could leave about two thirds of the country’s nuclear plants without power for one to two years.

Preventing a surge from a CME would be costly. With enough warning (at least a few hours, probably), power companies could shut transformers off entirely, turning them back on after the storm. But shutting down the grid on such a large scale would cost billions. To confidently do so, forecasting must be accurate.

Last October, NASA scientists announced its Solar Shield program to monitor solar eruptions and predict storms. Though a good step, the system uses a satellite that was launched in 1997 and designed to run just five years. No other country has anything similar, or as advanced.

Our backup systems aren’t in place yet, either. The Department of Homeland Security is funding the development of an emergency replacement transformer, but it won’t be field-ready for several years. Kappenman has developed a $100,000 capacitor to block storm-induced surges, but these are unproven in emergency situations. “A massive solar storm is a ‘low probability’ event the same way a 100-year flood is,” Thomas Popik, the author of the NRC petition, says. “Just as we build levees to protect against 100-year floods, we need to build protection against 100-year solar storms.”

ORS-1 cost the AF less than $100 million (that’s cheap for a spy satellite) and went from drawing board to launch-ready in about 30 months (also impressive). It’s headed for a 250-miles-high orbit that will be convenient for peering into the Af/Pak region where U.S. troops are operating. It sports no fancy new technology, but the same SYERS-2 sensor package and software that is carried by manned U-2 spy planes.

The launch marks the culmination of a shift in the way the U.S. military approaches its space recon technology and the strategic and financial costs associated with it. The ORS office has been given the task of shrinking the size and price tag associated with lofting reconnaissance hardware into orbit--a priority that unsurprisingly moved up the AF’s list about the same time China started testing anti-satellite missiles.

The idea is two-fold. For one, cheaper satellites means more satellites, which should eventually translate into satellites that are more responsive to troops on the ground. Right now, any old platoon in Afghanistan can’t just call in a satellite to provide intel on the ground. That will change. And of course, there’s those missiles. The military would like to make it cheaper, easier, and faster to put a satellite into orbit so if one gets shot down by an enemy force, another can quickly replace it. Make the satellites plentiful at a fraction of the cost of the missiles, and satellite warfare becomes uneconomical.

ORS-1 was scheduled to launch aboard its Minotaur last night, but the countdown was scrubbed due to scattered bad weather in the region. But if you're on the East Coast, you could be in for some pre-Independence Day fireworks at some point this week. Wallops will attempt to launch ORS-1 every evening from now through July 10 until the weather agrees, meaning East Coast-ers could catch a glimpse of a brilliant sunset rocket ascent tonight or sometime in the next few days. The three-hour launch window is expected to re-open tonight at 8:28 EST.

[Space, Danger Room]

ORS-1 cost the AF less than $100 million (that’s cheap for a spy satellite) and went from drawing board to launch-ready in about 30 months (also impressive). It’s headed for a 250-miles-high orbit that will be convenient for peering into the Af/Pak region where U.S. troops are operating. It sports no fancy new technology, but the same SYERS-2 sensor package and software that is carried by manned U-2 spy planes.

The launch marks the culmination of a shift in the way the U.S. military approaches its space recon technology and the strategic and financial costs associated with it. The ORS office has been given the task of shrinking the size and price tag associated with lofting reconnaissance hardware into orbit--a priority that unsurprisingly moved up the AF’s list about the same time China started testing anti-satellite missiles.

The idea is two-fold. For one, cheaper satellites means more satellites, which should eventually translate into satellites that are more responsive to troops on the ground. Right now, any old platoon in Afghanistan can’t just call in a satellite to provide intel on the ground. That will change. And of course, there’s those missiles. The military would like to make it cheaper, easier, and faster to put a satellite into orbit so if one gets shot down by an enemy force, another can quickly replace it. Make the satellites plentiful at a fraction of the cost of the missiles, and satellite warfare becomes uneconomical.

ORS-1 was scheduled to launch aboard its Minotaur last night, but the countdown was scrubbed due to scattered bad weather in the region. But if you're on the East Coast, you could be in for some pre-Independence Day fireworks at some point this week. Wallops will attempt to launch ORS-1 every evening from now through July 10 until the weather agrees, meaning East Coast-ers could catch a glimpse of a brilliant sunset rocket ascent tonight or sometime in the next few days. The three-hour launch window is expected to re-open tonight at 8:28 EST.

[Space, Danger Room]

The animation below is stitched together from images captured by the US GOES 13 satellite, which is on an orbital path somewhat to the west of Iceland. For the purposes of snapping images of a massive ash plume blasting through the cloud layer, that positioning might be ideal, as with the horizon in sight you can get a better feel for just how high this plume is rocketing (it’s 7 miles up right now).

Still not feeling the magnitude? That blue line that appears in the final frame shows the outline of Iceland. Yeah, it’s a big plume.

[Bad Astronomy]